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Biomedical subjects

J Ehlers

Publications and source records attributed to J Ehlers.

11 recordsLinked to original sources

Rapid estimation of chromosomal damage in yeast due to the effects of environmental chemicals using pulsed field gel electrophoresis.

We present a procedure to rapidly estimate the damage to yeast chromosomes by toxic chemicals. This procedure employs the following steps: incubation of yeast cells with the chemicals, DNA preparation in an agarose matrix, separation of chromosome-sized DNA molecules into reproducible band patterns by pulsed field gel electrophoresis, and quantification of the intensity of chromosomal bands by densitometry. Saccharomyces cerevisiae cells have been treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and cis-Platinum(II) diamminedichloride (cisPT), both of which are known to interact with DNA, and trichlorethylen (TCE), for which such an effect has not been shown in yeast. Treatment of cells with MNNG and cisPt led to an impairment of the intensity of the band pattern to an extent dependent on the concentration of the chemicals applied. For TCE a similar effect could not be discerned. This procedure will be useful as a screening test for the estimation of the biological hazards of toxic chemicals.

Chromosomes, Fungal

[Epidemiologic studies of the detection of viral infection agents in calf losses in the Weser-Ems region].

In 961 calves up to an age of 6 months which were sent to the animal health center in Oldenburg between March 1987 and March 1990 for necropsy the results of determination of different viruses were calculated: BVD-, rota-, corona-, parainfluenza-3- (PI-3)-, bovine herpes-1 (BHV-1)- and bovine respiratory syncytial virus (BRSV). In 122 and 104 randomly collected health calves of 22 farms antibodies against BRSV and bovine adeno virus-types 5, 7 and 8 were determined. 50.1% of the necropsied calves were one and two weeks old. In this group in 40.2% rotavirus and in 19.0% coronavirus could be isolated. All over the calves the frequencies of isolated viruses were 13.3% for BVDV, 4.6% for BRSV, 3.2% for BHV-1, and 2.1% for PI-3. The percentages of positive findings for rota- and coronavirus increased up to 7 days after birth, and thereafter both decreased. The frequencies of BVDV and BRSV were higher in older groups. The frequency of PI-3 was low and remained constantly. Infections with rota-, corona- and with both viruses were accompanied by BVDV in 11.3, 5.3 and 14.3%, respectively. Against bovine adenoviruses and BRSV in the first 8 weeks and after 14 weeks of life in more than 70% of the calves antibodies were detected.

Animals

Alkaline phosphatase activities and progesterone concentrations in uterine flushings of dairy cows: side-effects and variations during oestrous cycle.

After evisceration at an abattoir, both uterine horns of barren cows were flushed using 30 ml of Dulbecco's phosphate buffered saline (trial 1, 49 cows) or 10 ml sterile saline (0.9%, trial 2, 22 cows). Blood was collected from the animals' hearts (trial 2). Activities of alkaline phosphatase and progesterone concentrations (trial 2) were determined in uterine flushings and serum. In uterine flushings, both parameters exhibited a significant cyclic pattern, while in serum, only progesterone concentrations showed cyclic fluctuations. Alkaline phosphatase activities in uterine flushings taken ipsilateral to a corpus luteum were significantly higher than in materials obtained from the contralateral horn during dioestrus and prooestrus. A similar tendency was obvious for progesterone concentrations. All parameters but serum alkaline phosphatase activity were positively correlated with each other. The results suggest a close relationship between a progesterone secreting corpus luteum and metabolic as well as hormonal parameters evaluated in flushings of the ipsilaterally situated uterine horn. Transfer of progesterone via the blood vessels and lymphatics within the ligamentum latum uteri may be the cause of the between-side-effects detected.

Alkaline Phosphatase

Effects of camostat, a synthetic protease inhibitor, on endocrine and exocrine pancreas of the rat.

The effects of chronic oral treatment of rats with 400 mg/kg body weight camostat, a synthetic protease inhibitor, on weight gain and both pancreatic exocrine and endocrine secretion were studied and compared with pair-fed controls. Administration of camostat was found to result in a lower weight gain than in untreated rats fed ad libitum because of reduced food intake. The pancreas of treated rats showed hypertrophy and hyperplasia with significantly higher total contents of amylase, lipase, trypsinogen and chymotrypsinogen than that of pair-fed controls. The specific activity of lipase, trypsinogen and chymotrypsinogen remained unchanged but the specific activity of amylase was significantly lower than in pair-fed controls. Stimulation of pancreatic enzymes with CCK 8 in treated rats resulted in a greater output of proteases, no difference in secretion of lipase and a lower secretion of amylase than in pair-fed rats. Glucose-dependent insulin secretion was also significantly lower in camostat-treated rats than in controls. This effect could be reversed by gastric inhibitory polypeptide. After termination of treatment with camostat all enzymes were normalized within 14 d. Our results on the hypertrophied pancreas of rats suggest preferential synthesis and secretion of protease at the expense of amylase and diminished sensitivity of insulin to stimulation by glucose. All effects of camostat on the pancreas were reversible.

Amylases

Comparison of tissue reaction to nylon and prolene sutures in rabbit iris and cornea.

The tissue reaction in rabbit iris and cornea to prolene suture is equivalent to the tissue reaction to nylon suture. The prolene suture retains its tensile strength indefinitely and this may make it particularly useful in situations where a permanent suture is desired, such as in refractive keratoplasty, scleral buckle, or to suture an intraocular lens to the iris. The prolene suture also has a greater elasticity and this property may be advantageous in some clinical applications. We feel that a clinical study on humans is now warranted and we have started such a study.

Animals

Green tobacco sickness: occupational nicotine poisoning in tobacco workers.

In this study the authors describe the investigation of a 1992 outbreak of green tobacco sickness, a form of nicotine poisoning from dermal exposure, among 47 tobacco workers in a five-county region of central and south-central Kentucky. Cases were identified through medical record searches at participating hospitals, as well as from reports submitted to the Occupational Health Nurses in Agricultural Communities program. A case-control study was undertaken to assess risk factors for green tobacco sickness. In a 20-min telephone interview, 40 cases and 83 controls responded to questions contained in a questionnaire. In 1992, 47 persons (3 were under age 16 y) in the study region sought medical treatment for green tobacco sickness. Twelve persons were hospitalized and 2 required intensive-care treatment. The crude incidence in 1992 was 10.0/1,000 tobacco workers. In 1993, 66 cases (7 were under age 16 y) of green tobacco sickness were identified in the study region (i.e., annual incidence of 14.0/1,000). A case-control study demonstrated that ill workers were younger, and were more likely to have worked in wet conditions, compared with workers who were not ill. Green tobacco sickness is a common problem among tobacco workers that may be prevented by avoiding work in wet tobacco or by use of protective clothing. Children younger than 16 y of age represented 9% of the green tobacco sickness cases in 1992 and 1993. Current occupational safety and health laws do not address protection of tobacco workers with respect to green tobacco sickness.

Adolescent

[The social function of the hospital].

Issuing from the statements to the change of the social institution hospital in the course of history the experiment is undertaken to outline the social function of the hospital on the conditions of the developed socialist society.

Aged